Yarn texturing apparatus and method



y 1965 E. K. MCINTOSH ETAL 3,

YARN TEXTURING APPARATUS AND METHOD Filed Aug. 21, 1965 INVENTORS EUELLK. McINTOSH WILLIAM H. HILLS ATTOR Y 3,192,597 YARN TEXTURING APPARATUSAND METHGE Eueil K. McIntosh and Willim H. Hills, Pensacola, Fla,assignors to Monsanto Company, a corporation of Delaware Filed Aug. 21,1963, Ser. No. 303,504 7 Claims. (Cl. 28-1) The present inventionrelates to yarn texturing wherein yarn is provided with latent crimps bypassing through meshed gears, and more particularly to such texturingwhich is adapted for texturing textile denier yarns.

In a known method and apparatus for texturing thermoplastic yarns, astypified by Bromley et al. US. Patent 3,024,516, yarn is simultaneouslydrawn from a draw pin and crimped by multiple passes through a set ofmeshed gears in cooperation with a separator roll. The yarns typicallyprocessed according to the Bromley et a1. apparatus ranged from nearly athousand to several thousand total denier. The individual filamentdeniers were typically sixty denier per filament (DPF) before texturing,and about twenty DPF after texturing. Due to the heavy denier yarnsprocessed in the Bromley et a1. apparatus, several passes of the yarnaround the gears were necessary to get enough traction to draw yarn.Since the individual filaments had a large denier, relatively coarsepitched gears and comparatively wide clearance between the gears wasnecessary, which increased the need for several passes through thegears.

When textile denier yarns (those having total denier ranging up to a fewhundred and filaments with about 1520 DPF before texturing and about 2-7DPF after texturing) are gear textured, it has been found to be possibleto texture the yarn in a single pass through the gears, and thus toconsiderably simplify the necessary apparatus and the yarn stringup.According to the present invention, gears having a relatively largenumber of teeth per inch are used. These gears are closely meshed inorder to provide adequate crimping action and enough traction to drawthe yarn. The yarn is formed into a filament sheet just prior to itspassage through the meshed portion of the gears in order to avoid unevenrunning and breaking of filaments by the gears. These results areachieved by the apparatus to be described.

Accordingly, a primary object of the invention is to provide a methodand apparatus for texturing yarn.

A further object is to provide such method and apparatus wherein theyarn is textured by a single pass through meshed gears.

A further object is to provide such a method and apparatus wherein thegeometry is arranged so as to require a minimum number of parts and asimple stringup.

Other objects of the invention will in part be obvious and will in partappear hereinafter.

The invention accordingly comprises the several steps and the relationof one or more of such steps with respect to each of the others, and theapparatus embodying features of construction, combinations of elementsand arr-angements of parts which are adapted to effect such steps, allas exemplified in the following detailed disclosure, and the scope ofthe invention will be indicated in the claims.

For a more complete understanding of the nature and objects of theinvention, reference should be made to the following detaileddescription taken in connection with the accompanying drawing, in whichFIGURES 1 and 2 are fragmentary schematic perspective views of apparatusaccording to the invention.

Referring now to FIGURE 1, yarn 20 from a spin cake 22 or otherconvenient source is fed by driven nip rolls 24 to a brake or othersnubbing device 26, illustrated United States Patent 3,192,597 PatentedJuly 6, 1-965 as an electrically heated hot pin. A conventional guide 27may be provided to guide yarn 20 to nip rolls 24. Yarn 26 then passesthrough meshed gears 28 and 30, which are positively driven so as tostretch or draw the yarn in the region between pin 26 and the gears.Yarn 20 then passes through a pigtail guide 32 to a suitable windupmechanism 34, which may be of any desired type.

In order to positively locate the point of contact between yarn 29 andgears 28 and 30 while reducing the number of auxiliary guides to theminimum, the axis of pin 26 is skewed with respect to the axes of gears28 and 3t Advantageously pin 26 lies in the plane in which the gearsrotate, and is perpendicular to the path of yarn 20.

The filaments of yarn 20 during passage'around the draw pin are formedinto a filament sheet, the transverse dimension of which isperpendicular to the axes of the gears. Passage of the yarn as a roundbundle or as a filament sheet thus oriented directly through the meshedportion of the gears could result in uneven running and breaking of thefilaments by the gear teeth since the gears are closely meshed.According to the present invention, gears 28 and 36 are mounted so thatthe axis along which the yarn travels between pin 26 and the gears formsan acute angle with a perpendicular line between the gear axes, causingyarn 26 to Wrap around part of the periphery of one of the gears in anarc extending over several degrees before contacting the remaining gear.This rearranges the filaments into a filament sheet spread on theSurface of the first gear contacted and having its transverse dimensionparallel to the gear axes, as best illustrated in FIGURE 2, so that theyarn may pass through the meshed portion of the gears without breakage.Advantageously, draw pin 26 is so mounted that a line perpendicular tothe axes ofgears 28 and 39 forms an angle greater than 10 with the axisof draw pin 26. Since the yarn passes through the meshed portion as afilament sheet, the number of gear teeth per inch of gear circumferencemay be increased and the clearance between the gears may be reduced.These factors produce suificient traction to draw and crimp the yarn ina single pass through the gears without danger of cutting the filaments.

In a specific example for texturing yarn of nylon 66 having thirteenfilaments and forty total denier after texturing, the angle between theyarn axis and a perpendicular line between the gear axes was 45 Gears 28and 39 had diameters of 1% inches and 2 /8 inches, respectively, andeach gear had 64 teeth per inch of diameter. Draw pin 26 waselectrically heated to about C., and the apparatus was designed toprovide a draw ratio of between 2.25 and 2.50. The yarn ran smoothlythrough the apparatus, and possessed excellent bulking characteristics.

It may be seen from the above written description and the accompanyingdrawing that there has been disclosed an efiicient and simple method andapparatus for texturing yarns. By wrapping the yarn about a portion ofthe periphery of one of the gears before the yarn enters the meshedportion of the gears, the yarn is formed into a filament sheet properlyoriented to run smoothly through the gears. This permits a greaternumber of gear teeth per peripheral inch, with closer spacing betweenthe meshed teeth than would otherwise be possible, and in turn permitstexturing and drawing the yarn in a single pass through the gears. As anadded feature of the invention, orienting the draw pin 26 to be skewedwith respect to the axes of gears 28 and 3t) positively locates the yarnon the gears, preventing the yarn from Wandering off the gears. Sincethe yarn can be drawn and textured by a area-ear :3 single pass throughthe gears, it is possible to eliminate the separator roll which would berequired with multiple passes through the gears. The disclosed apparatusis simple, and provides an economical and reliable process for producingtextured yarns.

It will thus be seen that the objects set forth above,

among those made apparent from the preceding description, areefficiently attained and, since certain changes may be made in carryingout the above process and in the construction set forth withoutdeparting from the scope of the invention, it is intended that allmatter contained in the above description or shown in the accompanyingdrawing shall be interpreted as illustrative and not in a limitingsense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

Having described our invention, what we claim as new and desire tosecure by Letters Patent is:

1. Apparatus for bulking a muiti-filament yarn, comprising incombination:

(a) a pair of driven meshed yarn-crimping gears,

(b) a source of multi-filament yarn to be bulked, said source supplyingyarn to be passed through said gears,

(c) a snubbing mechanism positioned between said source and said gearsfor exerting a redeterrnined braking effort on said yarn whereby saidyarn is drawn in the region between said gears and said snubbingmechanism,

(d) said snubbing mechanism being oriented with respect to said gears sothat said yarn wraps around part of the periphery of a first of saidgears and forms into a substantially flat filament sheet on saidperiphery before entering into the region where said gears mesh,

(e) and yarn takeup means for collecting said yarn after a single passthrough said gears.

2. The apparatus defined in claim 1 wherein said snubbing mechanism hasan axis skewed with respect to the axes of said gears sufiiciently topositively locate the point at which said yarn contacts said gears.

3. The apparatus defined in claim 1, wherein the braking eiiort exertedby said snubbing mechanism and the closeness of the meshing of saidgears are proportioned to draw said yarn to between 2.25 and 2.50 timesits original length.

4. Apparatus for bulking a multi-iilament yarn, comprising incombination:

(a) a pair of driven meshed yarn-crimping gears,

(b) a source of multihlament yarn to be bulked, said source supplyingyarn to be passed through said gears,

(c) and a heated draw pin mounted between said source and said gears,

(d) said yarn being wrapped about said draw pin whereby said yarn isdrawn in the region between said gears and said draw pin.

(e) said draw pin being skewed with respect to the axis of said gearssufiiciently .to positively locate the said yarn, and being mounted withrespect to said gears so that said yarn wraps around part of theperiphery of a first of said gears and forms into a substantially fiatfilament sheet on said periphery before entering into the region wheresaid gears mesh.

5. A method for texturing yarn in a single pass through a pair of meshedcrimping gears, comprising in combination:

(a) drawing said yarn from a heated draw pin having its axis skewed withrespect to the axes of said gears,

(b) and passing said yarn around part of the periphery of a first ofsaid gears so that said yarn forms a filament sheet on said peripherybefore entering into the region where said gears mesh.

6. Yarn treating apparatus comprising in combination:

(a) a pair of meshed yarn-crimping gears rotating in a plane, (b) a hated draw pin having an axis positioned in said plane,

(0) a line in said plane joining the aXes of said crimping gears formingan angle with said draw pin axis greater than 10.

7. The apparatus defined in claim 4, further comprising yarn takeupmeans for collecting said yarn after a single pass through said gears.

References Cited by the Examiner UNITED STATES PATENTS 2,983,799 6/61Atwell 28-1 3,009,308 11/61 Bromley et al. 28-713 3,024,517 3/62 Bromleyet al. 28-1 3,041,706 7/62 Bromley et al. 28-72 3,116,531 1/64 Hills etal. 28-1 3,137,911 6/64 Bromley 28-1 FOREIGN PATENTS 669,049 8/63Canada.

DONALD W. PARKER, Primary Examiner.

1. APPARATUS FOR BULKING A MULTI-FILAMENT YARN, COMPRISING COMBINATION:(A) A PAIR OF DRIVEN MESHED YARN-CRIMPING GEARS, (B) A SOURCE OFMULTI-FILAMENT YARN TO BE BULKED, SAID SOURCE SUPPLYING YARN TO BEPASSED THROUGH SAID GEARS, (C) A SNUBBING MECHANISM POSITIONED BETWEENSAID SOURCE AND SAID GEARS FOR EXERTING A PREDETERMINED BRAKING EFFORTON SAID YARN WHEREBY SAID YARN IS DRAWN IN THE REGION BETWEEN SAID GEARSAND SAID SNUBBING MECHANISM, (D) SAID SNUBBING MECHANISM BEING ORIENTEDWITH RESPECT TO SAID GEARS SO THAT SAID YARN WRAPS AROUND PARTS OF THEPERIPHERY OF A FIRST OF SAID GEARS AND FORMS INTO A SUBSTANTIALLY FLATFILAMENT SHEET ON SAID